How to get the time zone name for a CLLocation - dst

Question

I have an application that uses a CLGeocoder to forwardGeocode a placemark from an address string. The CLPlacemark response contains a CLLocation which gives me GPS coordinates.
The only way to create an NSTimeZone seems to be by using the correct Time Zone Name. It is important to point out that I am not using the current location of the device, so [NSTimeZone localTimeZone] will not work for me.
Is there a way to get the timezone name for the CLLocation so that I can create an NSTimeZone correctly?
NOTE: I have been using timeZoneForSecondsFromGMT but that never contains correct DST data, so it is not helpful for me.

Answer 1

You should use https://github.com/Alterplay/APTimeZones to get NSTimeZone from CLLocation. It also works with CLGeocoder.

Answer 2

since iOS9 it should be possible direclty using CLGeocoder as specified here: https://developer.apple.com/library/prerelease/ios/releasenotes/General/WhatsNewIniOS/Articles/iOS9.html
Search results for MapKit and CLGeocoder can provide a time zone for the result.

Answer 3

I found an interesting approach using CLGeocoder, which I put into a category on CLLocation. The interesting part looks like this:
-(void)timeZoneWithBlock:(void (^)(NSTimeZone *timezone))block {
[[[CLGeocoder alloc] init] reverseGeocodeLocation:self completionHandler:^(NSArray *placemarks, NSError *error) {
NSTimeZone *timezone = nil;
if (error == nil && [placemarks count] > 0) {
CLPlacemark *placeMark = [placemarks firstObject];
NSString *desc = [placeMark description];
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:#"identifier = \"([a-z]*\\/[a-z]*_*[a-z]*)\"" options:NSRegularExpressionCaseInsensitive error:nil];
NSTextCheckingResult *result = [regex firstMatchInString:desc options:0 range:NSMakeRange(0, [desc length])];
NSString *timezoneString = [desc substringWithRange:[result rangeAtIndex:1]];
timezone = [NSTimeZone timeZoneWithName:timezoneString];
}
block(timezone);
}];
}
Usage is like this:
CLLocation *myLocation = ...
[myLocation timeZoneWithBlock:^(NSTimeZone *timezone) {
if (timezone != nil) {
// do something with timezone
} else {
// error determining timezone
}
}];
Despite requiring a network connection and working asynchronously, I have found this to be the most reliable way of getting the time zone for a location.
EDITED YEARS LATER
This answer hasn't aged well since the timeZone property was added to CLPlacemark in iOS9 (thank you Ortwin Genz). Here's an updated category method:
-(void)timeZoneWithBlock:(void (^)(NSTimeZone *timezone))block {
[[[CLGeocoder alloc] init] reverseGeocodeLocation:self completionHandler:^(NSArray *placemarks, NSError *error) {
NSTimeZone *timeZone = nil;
if (error == nil && [placemarks count] > 0) {
CLPlacemark *placeMark = [placemarks firstObject];
timeZone = placeMark.timeZone;
}
block(timeZone);
}];
}